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/**
 * Chunker API can be used to slice up the file content according
 * to specific logic. It is designed with following goals in mind:
 * 
 * 1. Stateless - All the state manangement is handled by the consumer, meaning
 *    it is consumers responsibilty to slice from the buffer to get a new slice.
 *
 * 2. Effect free - Since chunker does not read from the underlying source
 *    consumer is free to perform multiple calls while moving buffer offset
 *    or it could read more bytes and perform reads afterwards.
 *
 * 3. Doesn't manage resources - Chunker does not manage any resources, this
 *    guarantees that chunker can not use more memory than desired by consumer.
 */
export interface Chunker<T extends Readonly<unknown>> {
  /**
   * Context used by the chunker. It usually represents chunker
   * configuration like max, min chunk size etc. Usually chunker implementation
   * library will provide utility function to initalize a context.
   */
  readonly context: T
  /**
   * Chunker takes a `context:T` object, `buffer` containing bytes to be
   * chunked and `ended` flag that tells it if more bytes could be made
   * available in the followup calls. Chunker is supposed to return positive
   * integer constituting number of bytes (from the start of the buffer)
   * that contain next chunk. If returned number is `0` that signifies that
   * buffer contains no valid chunks. Returning negative numbers is not allowed.
   *
   * **Note:** Chunker MAY return `0` even if `ended && buffer.byteLength > 0`,
   * it is consumers responisibility to handle remaining bytes, despite it not
   * been a chunk.
   */
  cut(context:T, buffer:Uint8Array, ended:boolean):number
}

export function mod(x: u64,  p: u64): u64 {
  while (degree(x) >= degree(p)) {
      var shift = degree(x) - degree(p);
      x = x ^ (p << shift);
  }
  return x;
}

export function mod(x: u64, p: u64): u64 {
  let shift: i32;
  let dp = degree(p);
  while ((shift = degree(x) - dp) >= 0) {
    x ^= p << shift;
  }
  return x;
}